Weird thing just happened. I added a new document to a manuscript and when typing, all letters are in caps. Caps lock is not on. It's not happening in any other app, just in Scrivener and just in a new document. I deleted the problem document, opened another an the same thing happened. I tried cutting/pasting lower-case characters from another document which worked, but still...it's annoying and I don't want it to keep happening. Any help in Scrivenerville?
You're probably in Script Mode.
In my version of Scrivener (Mac) you can press command-8 to switch back and forth between modes. (I.e. prone opportunity for mishaps...)
You should also be able to uncheck it by selecting:
Format > Scriptwriting > Script Mode.
It should be checked if this is your problem.